A flex lane is a traffic management lane that operates dynamically to help manage congestion and improve traffic flow during peak periods or emergencies. There are two common types of flex lanes:
- Directional Flex Lanes: These are additional lanes that carry traffic in only one direction at a time and can switch directions based on traffic demand. For example, a two-lane roadway adjacent to existing lanes may carry northbound traffic during most of the week and switch to southbound traffic on certain days or during emergencies. Safety features like automated gates, barriers, and dynamic signs are used to prevent wrong-way entry and ensure safe operation
- Dynamic Shoulder Use Flex Lanes: These use the highway's inside median or outside shoulder as an extra travel lane during peak traffic times, typically morning and afternoon rush hours. Overhead signs indicate when the lane is open (green arrow) or closed (red X), and drivers must merge out when the lane closes (yellow X). These lanes are separated by solid yellow lines and are not restricted by vehicle occupancy but often exclude heavy trucks and trailers. This approach improves travel time reliability without expanding the highway footprint
In summary, flex lanes are flexible, time- or demand-based lanes designed to increase roadway capacity and reduce congestion by allowing temporary use of shoulders or dedicated lanes that change direction or availability according to traffic needs. They are controlled by dynamic signage and safety systems to ensure proper and safe usage
